Dynamo-electric machine.



W. F. DAWSON.

DYNAMO ELECTRIC MACHINE.

APPLDATION FILED JULY l5. 1908.

919,547. Patented Apr. 2?, 1909 2 SHEETS-SHEET 1` F. DAWSON.

DYNAMO ELEGTRLC MACHINE. A'PPLIOATIO 'N FILED JULY 15, 1908.

l l /m/entar: )7M/am FDM/sof?,

Patented A111127, 1909.

2l SHEETS-SHEET 2.

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WlLLIAM F. DAWSON, OF RUGBY, ENGLAND, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A OORORATION OF NEW YORK.

No. einer?.

Application ed July 15, 3.9538; @arial No. 43,592.

To all ywhom it may concern:

Be it known thet l, WiLLiAM Iv'DAi/vson, e citrzen of the United States, residing at Rugby, Englzrnd, lieve-invented certain new sind nseiul .improvements in Dynamo-Electrie lliireliines, of .vnich the following is e.

speeieetion.

lll/ invention relates to dynemo-eleetrio machines, and more pertieiilerly to the enrrent collecting end slie1l-eiicuiting devices ernployed'in induction inotors having coil wound retors. f

, The oiiieet off my invention is to ohviete' the loss ol energy occurring in the brushes of snfoh machines e'fter the winding has been slior ironited, md iilso'to avoid the weer et the collec-.tor rings and brushes caused by the brushes 'being left intheir operntivfe en when not required, i

,teler-e, in machines of the above rnenl type, here heen used lor reing' the brushes 7from the collector rings, in ifhieh insulating wedges or pins :ire innnder the tangential copper brushes so to lift rhein out oi' eontnrt with the end also with seine forms of enrhon holders the brush holders nre so mounted 'that the); nniv he roailed :wmv from the collector The 'lirst ol' these urinngeinents hesv necessitated the use oi' Copper brushes which is objectionable, while the second errmigeinent is subject to the oli- (ieelion that when the brush holders are :renin returned to their oper-n tive positions there is no 2^siiiz11iee that l'hev will tnlie no ltheir origine. i l full Contar-t with the slip rings.

lily Iinvention. eonsiss in providingl :Mln-usi: inovinfr nwehnnisin whirh will li'it the brushes 'when rerpiired in n snlislnntinllv redinl diree'iion i'roni the rollerlor rings \\'iiliont nl* the posiiion ol ille lirnsh holders so ihn-L 'hen the l hes nre reim led Contact willi the r1 K they' will :rionee resume their normali oper-nii 'e positions.

"lt i oi niv invention will he edler .ienrrn pointed ont with. pnrlienlnrity in he claims annexed ro and forming" n port of this speellille on. For e better sinderstznnlingl` ol niv ion7 however, reference ning he hed ro ille following?r description tnlien in connecwith the erwin!- which lfignre l is n, lon;`

inv/inurl elevolion. partly .l posilions :ind liringr the hrzidws into Specification. of Letters Potent.

Patented .April 27, 1909.

in section, of :i current collecting and shor Cireuiting device embodying my invention; Fig. 2 is e plan View of the saine with the outer eesinff removed 3 Fig. S is en end eleration; one Fig. el. is en endl vien' with the end plete of the casing removed.

Referring to the drawings, the collec-tor rings 1 nre mounted on the end of the shaft 2, and n. easing 3 ineloses the collector rings end the hru'sh carrying mechanism. This easing is provided with hinged portions to enable the meohenisn'i to be readily inspected. The brush lifting device is e. lever mechanism comprising e lever 6 which is rigidly secured to the end 5 of n rod 4 which has its 'exis parallel to the eXis of the shaft find is journeled in the ends ol the easing'. The rod Ll is rotated by nieirns of this lever (l. The lever 6 is provided Willi on opernlino' handle 7 whieh is adopted to inove throl y e eertnin are and to he looked :it either end of its movement. The locking; mechanism which l have preferred to use comprises e spring-pressed pin S projeatingv from the end ol the handle and adapted to he enga-ged hy the hand of the operator4 This pin has :in enlarged portion 9 et its inner end 'which projects into en aperture l() formed in the plete ll over wlnrh the handle 7 moves. The plete is nrovided at both ends willi apertures i() ot the saine diameter, the two being joined by en ore-shaped slot l2, the width oi which is insufl'leient to allow the enlarged portion Q of the pin to pass but snilieient to allow rire pin itself to pass through. in order to inove the lever (S the iin innst he iressed inwzrrdlv so ihn-t the enlarged portion Q passes inward through the plete ll into the spa-Ce lielnnd it. The han( le can then he moved, with the holly or the pin projeming"y lhrongih the nre-slieped slot if, unid il reairhr-s the other end ol the slot, when on releasingr the pir. the sprintf l? returns the enla O mio the operi-ure lorined :it that end,

The rod #l has riggidlyiixed to it.y tiro or portion 9 oi the pin' bet-Ween the insulating rod and the arms cup-shaped rece taele 2 9.

17 is preferably a lost motion one, as is clearly seen in Fig. Ll. l have used this lost motion device to allow the brushes to adjust themselves for Wear.

lilhen it is desired to remove the brushes from the collector rings, the machine being in operation, the pin 8 projecting from the operating handle 1s depressed and the open atinfT handle and', consequently, the end of the lever 6 is moved from one end of the arc-shaped slot 12 to the other, thereby Icausing the rod 4 to rotate carrying with it vthe cranks 14 and the insulating rod 15.

Movement of the lever 6 thus causes' the brushes 18 tobe lifted out of their holders 19 in a direction substantially radial to the collector rings.

The device which l have shown for shortcircuiting the collector rings consists of a contact member 2G which is shown in the form of a cylinder adapted to be inserted or Withdrawn from a cylindrical aperture which is formed in the end of the rotor shalt This contact member 120` must rotate with the shaft because of the pin 26 which 'lits in the slot The contact member 20 has three arms 28 which move in and out ol' the Earli of these receptacles 29 is olted to one ol the collec tor rings by means of rods 30. ln starting the induction. motor this cont-act member is partially withdrawn until the handle occupies the position shown in dotted lines in Fig. 1 so as to open the short-circuit. lYhen the motor has attained the proper speed, the contact member 20 is inserted to its full extent in the cup-shaped receptacles '29 so as to short-circuit the rotor windings. in order to interlock the short-circuitingr device with the brush lifting mechanism, VI have provided the lever 6 with a slot 21 through-which the handle 22 of the contact member passes. The stem 23 of the contact carrying member which projects through the outerend ol the casing is made of two different diameters and when thecontacts areshort-circuited only a portion 24 which is `of smaller diameter brojects from the casing.l lhen the contact member is Withdrawn the portion 25 of the larger diameter also projectsf The slot 21 enlarged at 31 so as to allow the portion 25 of the stem to pass through it. llllhen the short-circuiting deviceis in this position it prevents the operating handle of the brush lifting mechanism from being moved. lt will thus-be seen that whenthe contact member 2 0 short-circuits the rotor'windingsthe brushes 18 may be withdrawn andmreplaced on the collector rings at will, but Whilel they l are Withdrawn it is impossible for the contact member to be moved so to break the short circuit because in this position the enf larged portion' 25 of the stern ol the Contact member is inthe path of the reduced portion of the slot 21 in the lever, thus forming a simple and eliicient interlock bclwccu the two.

l desire it to be understood that my invcn tion is not limited to the particular coustruction and arrangement described, and l aim in theappended claims to cover all modifications which do not depart from thc spirit ol my invention.

llhat l claim as new and desire to secure by Letters Patent of the United States, is zl. In combination, a set of rotating collector rings, brushes therefor, brush holders for said brushes, a device for short-circuiting said collector rings, means for moving the shoitcii'cuiting device into and out Aof the position in which it short-circuits Athe collector rings, and means for moving the brushes into and out of said brush holders in a substantially'radial direction.

2. ln "combination, a of rotating collector rings, rusnes therefor, brush holders for said brushes, a device for short-circuiting said collector rings, means for ,moving the short-circuiting device into andbut of the position in which it short-circuits the collector rings, and means for m'oving thehbrushes into and out of said brush holders comprising a rod, crank members, fastened .to said rod, a second rbd mounted `between said crank members, and arms to which said brushes are fastened mounted onsaid second rod.

3. ln combination, a set of rotating' collector rings, brushes therefor, brush holders for said brushes, a device for short-circuiting said collector rings, means for moving the short-circuiting device into and out of the position in which it-shortecircuits the collector rings, and means for moving ythe brushes into and out of said brush holdersycomprising a rod, crank members'fastened to said rod,'

an insulating rod mounted between said crank members, and arms mounted'onsaid insulating rod by means of a lost motion device, said brushes being fastened to sbid arms.

4. In combination, a set of rotating collec- 4;

tor rings, brushes therefor, brush hdlders for said brushes, a device for short-circuiting said collector rings, means for moving the short-circuiting device into and out of the position in which it short-circuits the eollector rings, means for moving the brushes into and-'out of said brush holders comprisingv a rod, ,a lever attached thereto, crank mem bers iastened to said rod,.an:insulating rod mounted between said crank members, and

arms t0 which said brushes are fastened mounted on said insulating rod, and interlocking connections between said lever and said means for moving the short-circuiting device so arranged that the brushes can only Vbe removed from the rings when the shortcircuiting device is in its operative position.

5. In combination, a set of rotating collector rings, brushes therefor, brush holders :forA

recY

siegte? seid brushes, e device lor short-eireuiting said collector rings, means for moving the short-eireuiting devioe'into and out of the position in whieh it short-circuits the colleci tor rings, means for moving the brushes into und out oi seid brush holders comprising a rod, e lever etteehed thereto, crank members fastened t-oseid rod, an insulating rod mounted between seid crank men'xbers, end arms to which said brushes are fastened mounted on said insulating rod, and interlocking connections betweenseid lever and said means for moving seid short-cireuiting device so erranged that it is impossible to remove the brushes from said rings while the short-cir @uiting device is ino eretive and also to open the short-circuit w ile the brushes are removed.

6. ln combination, s set oi' rotating colleetor rings, brushes therefor, brush holders for said brushes, a. deiiee for short-eircuiting said collector rings, ineens for moving the short-rirouiting device into und out of the position in which it short-Circuits the colleetor rings, und means for moving the brushes into and out oi seid brush holders comprising e rod, a lever attached thereto, means for limiting the movement of seid lever, crunk members fastened to seid rod, am insulating rod mounted between seid crunk members, und arms to which seid brushes ure fastened mounted on seid insulating rod.

7. In combination, e set of rotating collector rings, brushes therefor', brush holders for seid brushes, a, device for short-eireuiting seid collector rings, means for moving the short-eireuitin device into and out o vthe Aposition in which it short-circuits the colleetor rings, end means for moving the brushes into und out of seid brush holders comprising u' rod, a lever-attached thereto, means for limiting the movement of said lever, means Y.for locking seid lever et either end et its movement, orsnli members fastened to rod, en insulating rod mounted between said eriml; members, und :nms to which seid brushes are fastened mounted on seid insulating rod.

8. In combination, n set of rotating colleetor rings, brushes tlrerel'or, brush holders for seid brushes, u device for short-eireuiting seid collector rings comprising a Contact member having a stem with portions oi' two diflerent dimneters, and n lever mechanism 'for moving the brushes into und out ol' said brush holders, the lever ol' seid meehenisr having s slot enlarged et one end allowing the portion of the stem having the larger diameter to pass through,'therebjvr preventing the movement of said lever to lift the brushes when seid stem is in this position.

9. In combination, u set ol rotating collertor rings, brushes therefor, brush holders l'or said brushes, n. device for short-eirouiting seid Collector rings comprising s .eonturt member having u stem with portions of tvv@ di'fl'erent diznneters, means lor moving the brushes into and out ol' said brush holders eonmrising' :L rod, :1 lever attached thereto, erunl( members fastened to said rod, u second rod mounted between said crunk members, und arms to which Suid brushes ure fastened mounted on seid second rod, said lever having s slot enlurged at one end allowing the portion oi the stem having the larger dismeter to psss through it, therebyY preventing the movement of snid lever to lift the brushes when seid sten is in this position.

ln witness whereoi', l have hereunto set my hond this 25th dey ol' Jurre, i908.

ILLAB l?, DAWSON. Vitnesses:

CHARLES H. FULLER, J. A. FOSTER. 

